Thread-cutting device



Aug. am, w23. 1,@@41-,779

T. J. SHEARMAN THREAD CUTTING DEVI CE Filed April l2. 1921 2 Sheets-Shee't l ll 4Q 50 Aug. i4, 1923. flj@ T. J. SHEARMAN THREAD CUTTING DEVI GE Filed April 12. 1921 2 Sheets-Sheet 2 45 up with dirt but on the contrarythe struc- Patented Aug. 14, i923.

Retail@ Unirse stares Farrar carica.

J'. SI-IERMAN, 0F PHILADELPHIA, PENNSYLVANIA.

THREAD-CUTTING DEVICE.

, Application filed April 12, 1921. Serial No. 469,610.

To all 'whom t 'may concern:

Be it lrnown that l', THOMAS J. SHEAR- MAN, a citizen of the United States, residing at Philadelphia, in the county of Philadelphia and State of Pennsylvania, have invented certain new and useful Improvements in Thread-Cutting Devices, of which the following is aspecification.

Avnumber of thread-cutting devices have beenrinvented, prior Ato my, present invention, which are capable of threading the yends of pipesV in such manner that the threaded portions taper in the direction of the length of the pipes. These prior art devices,'however, are not completely satisfac-` xtory since they have a number of objectionable features. For example it sometimes occurs that small particles of metal lodge to the rear of one of the dies in a manner not .noticeable to the workman and after the threading takes, place there is an inaccurate cut which is likely to cause a leaky joint when the screw threaded end is fitted into va screw threaded opening. A still further disadvantage of said prior art structures is that dirt and lchips .often clog and prevent free movement of the dies in their guide- `ways and the removal of Vthis dirt is comparatively difficult and takes considerable of the time of the workman.

One object of my invention is to provide a threading device of the above general type in which the dies will accurately move in a predetermined path so that the cut will be under positive control at all times and furthermore that the dies will notaccidentally move out of their guideways.

Another object is to so construct the device of my inventionthat the dies can be quickly and easily removed and replaced; said dies being so made that by changing ,their position they will thread pipes of different diameters.

Y A further obj ect is to so `arrange the part-s that the guideways for the dies Vwill not clog ture will permit a free sliding movement of thedies at all times during the operae tion of the device. A

A still further object is to `make the` de- ',vicey in such manner that it will be Vwell balanced and can be easily manipulated to y accurately position it on a pipe to start a out. i

'f These objects, and other advantageous ends which will be described hereinafter, I y

'attain in the following manner, reference being had to the accompanying drawings in which- Figure 1 is a top plan view of a pipe threading device made in accordance with my invention, A

Figure 2 is a sectional elevation taken on the line 2-2 of Figure 1,

Figure 3 is a fragmentary section taken on the line 3-3 of Figure 2, i Figure 4L is a fragmentary section taken on the line lfl of Figure 1,

Figure 5 is a detail face view of one of the die retaining members,

. Figure 6 is a section taken on the line (aL-6 of Figure, i

Vdie guiding post made in accordance with my invention and showing the same secured in its retaining ring; the retaining ring being illustrated in section,

Figure 8 is .an elevation of one side of Figure 7, and

, Figure 9 is an elevation of the opposite side of Figure 7( Referring to the drawings, 1U represents a metallic head which includes'a central 1n` tegral depending nipple 11 which is exter-4 nally screw threaded 'as shown at 12. The external screw threads of the nipple 11 are adapted to screw into the internal screw threads 13 of a sleeve 1li. This sleeve 111 adjacent its bottom has an internal annular flange 1b, the inner surface of which is machine finished Vto a predetermined diameter to permit a clamping and centering collar 16 to be fitted therein so that it can be readily removed. Clamping collars 16 hav- Ving various internal diameters can be attached to the liange 15 to suit pipes of vaing screws 122L which extend through the sleeve; said clamping collars, 16 having holes into' which the inner ends of the clamping vscrews extend as clearly shown in Figure 2. These clamping screws 12a, when the pipe tobe fitted is inserted through the clamping collar, can be turned so as to jam against the outer surface of the pipe whileextending upwardly through the collar 16, sleeve 14 and nipple 11.

Thetop portion 17 ofthe head 10 at points, on opposite sidesof the axis of the nipple 11 has upwardly extending flanges 18 which are spacedV apart; the inner surfaces 19 ofsaid flanges on each side being lll) straight 'and parallel so as to provide guideways for the dies 21; said dies having opposite side surfaces parallel and accuratelv tting between the surfaces 19 so as to freely slide Yin the guideways. The guideways 20 extend without obstruction tothe end surfaces of the head and the top portion 17 of the head on either side of the axis of the nipple 11 has holes 23; said holes communicating with the bottoms of fthe guideways between the flanges 18. The

bottoms of the guideways adjacent the vsurfaces 19 are preferably-shaped to provide sliding ledges 21 upon which the dies 21 may slideV between surfaces 19 which hold 1them against 'lateral' movement. The top bart of the head adjacent the ledges, is

channeled, as shown at 25, `thereby providing rigidly supported lodges Vwith lnarrow fbearingsurfaees. l

A ring 26 rotatablylitsthe outer surface of `the sleeve 14: below the external ilange Y 27 of said-sleeve#said-external flange tormling a Vshoulderfor preventing` the ring 26 from moving upward relatively to vthe sleeve V111.' At Ya position below the ring 26 the have their axes slanting upwardly with respect tothe axis ot the nipple 11 -and pro ject through channel 25, the holesV 23, the "guideways 201 and holes 31 in theidies 21. The Aholes Y31 have a contour which registers with the curved cross sectional contour of vthe posts 30 and are located entirely bejtween vthe opposite ends 32 and 33 ot the dies 21. Thus when there is no relative rotatable movement between the head 10 andthe sleeve 14,4the'dies'21cannot nieve "inV their guideways either toward onroin the axis of the'nipple 11. l

rllhe flanges 18 or the head .10 have lateral projections 3d. the upperVV surfaces of Vwhich are preferably llush with the top 'edges of the surfaces 19. Cover members 35 bridge the tops ot the guideways 20 and extend across the tops of the dies 21. These cover members 35 are secured to the head 10 by means of screws 36; said screws itting within. tapped holes in the Vportions 34 of the -head 10. The screw 36 at one end olfthe cover member 35 .on each side extends through a hole 37 in said cover member while the screw 36 at the opposite end 'extends through a notch 38 in the cover member on each side 'of the device as clearly Ashown in `Figure 1j; the detail construction lo'fthesimilarly constructed cover members '35 being clearly shown in Figures 5 and 6.

Each `of the posts `30 iis-cut a-Wa'y at its opposite sides to provide parallel surfaces 39 and 40; said surfaces beingilat and also being Eparallel with the axis of the nipple 11. "lhe surface 210 of each post terminates at its `upper end in a shoulder 41; saidV shoulder being in such position as to be substantially on @the same level with the upper surface of the cover memberv 35 on each side et the'device. Thus when the 'parts are in their operative `assembled position, as shown in Figures 1 and 2, the Vupper endportions of the posts project Athrough slots 12 in lthe cover members V35;

said slots at their portions where the upper parts of the posts project therethrough being of a width vsubstantially `equal `tojthe thickness fof ``the posts between 'the surface I1 0 and theopposite 'sides of the post sothat `the shoulders 411 project over the top sur- -taces of the members-35 as clearly shown in Figure '2. The opposed surfaces 39 lterminate in shoulders L13 and serve to 1limit the downward movement of the "head by -engagement with the bottom portions of Ythe dies when the head'is rotated relatively to the sleeve 111 during v"the threading operation. Each ot the slots 42 adjacent Vone -end has an enlarged portion 421 correspond-Y' ving to the cross section of the posts above the shoulders 4-1-so that when it is desired to remove or Achange 'the Vpositions ol the dies 21 it is 4merely necessary Jtoremove the screws 36 Yfrom the'holes 37 'and loosen the other screws 36 after which lthe cover mem.

bers can -be lslid :to bring lthe enlarged portions *311 otjthe slots 12in-register .with the posts 30 and at thesame'time the 4notches 38 will be free of said llatter `mentioned `screws and the lmembersV 35 can lbe raised bodily, 'after which -the 'dies' rcan Ybe lifted f out et 'their 4gu'ideways.

rllhe ends 32 ofthe di'es'2-1 have threading portions 45 which lare adapted 'to threadV pipes o'fone diameter whilethe oppositefends 33 of the dies have threading portions 46 adapted, when the dies 'are reversed, to

`thread pipes of another. diameter.

.The head'latopposite sides 'of theposts 30 have dependi'ngarins 417 which have sockets 4.8 into which 'handle I'levers `can' be inserted so as to permit the rotation of Vthe head 10 to leltect the lthreading'of the end of a pipe which is-secur'edby the clamping screws 412 and which entends through `the 'collar 16, sleeve 121 and nipple 1'1 and between `Jthe .adjacent ends of the Vdies 21. During the threading action'the rotation of Ythe head vdue ftothe screw f'threaded connection between :the nipple 211 and sleeve 14 will cause the head 4"tofbe flowered Awith respect to the 'pipe fand the f dies will cut initially at their greatest depths and during the `downwardfino'vernent oii the head the dies under the controler the posts '30 -will tion of the length of the pipe. During this action the dies must move outwardly in a path prescribedby the slanting disposition Vof the posts and since the holes 3l in the dies slidably lit the curved cross section of the posts as shown in Figure 3, itis impossible for the dies to move inwardly during the downward movement of the head. The parallel straight surfaces 39 and LL() permit thercover members to move downward in a straight path parallel with the axis of the nipple l1 sc that these cover nieinbersdo not change their position relatively to said axis during the downward movement of the head.

By having the arms 47 depend as illustrated the line of handle connection is placed in a well balanced position so that thev device can Vbe readily handled` and ap- Y plied to a pipe and at the same time there is no obstruction of any character at the outer ends of the guideways. Therefore if there is any dirt which lodges on the ledges 24, during the outward movement of the dies, this dirt will merely be pushed over the ends of the guideways when it reaches the end surfaces 22. Furthermore any dirt which clogs inthe space 25 can either pass over the end 22 or drop through the nipple l1 or through thelioles 23. g i

lVhile I have described my invention as taking a particular form, it will be understood that the various parts of my invention may be changed without departing from the spirit thereof` and hence I do not limit myself to the precise construction set forth, but consider that I am at liberty to make such changes and alterations as fairly come within the scope of the appended claims. Y

Having thus described my invention, what I claim as new and desire to secure by Letters Patentis:

'1. A thread-cutting device including a rotatable head having flanges spaced apart and providing guideways; dies slidable inthe guideways; guide posts slanting relatively to the axis of the head and taking through the dies; members bridging the guideways and having slots adapted to embrace the guide posts, the parts of the guide posts which take through the slots having faces parallel to the axis of the head whereby the bridge members may move upwardly for downwardly without changing their distance from the axis o-f the head.

2. A thread-cutting device including a rotatable head having flanges spaced apart and providing guideways having ledges therein; dies having holes and slidable in said guideways on said ledges between the flanges, said head being cut away to provide spaces in said guideways below the ledges and having upright holes communicating with said spaces; guiding posts slanting relatively to the axis of said head and extend-- ing through said holes in the head and dies; and means for moving said head relatively to said posts in the direction of its axis and relatively to the length of said guiding means; substantially as described.

3. A thread-cutting device including a rotatable die-carrying head having flanges spaced apart and providing guideways; dies slidable within said guideways and having holes therein; guiding posts slanting relatively to the axis of said head and extending through said die holes above said guideways; and slotted members detachably secured to said head and bridging said guideways, said posts having cut-out portions providing surfaces parallel with the axis of said head and terminating in shoulders, said posts having said cut-out portions slidably .tting said slots so that the shoulders abut the upper surfaces of said members, said slots having enlarged portions movable into register with said posts to permit said members and dies to be lifted over said posts; substantially as described.

In testimony whereof I have signed my name to this specification in the p-resence of two subscribing witnesses.

THOMAS J. SHEARJMAN.

Witnesses:

CHAS. E. Porrs, ELIZABETH GARBE. 

